Continuous catalysis production method of PBT resin

A technology of PBT resin and production method, which is applied in the field of PBT synthesis, can solve the problems of accelerated hydrolysis, complicated post-treatment, and increased waste water treatment burden, etc., and achieves the effects of enhancing hydrolysis resistance, ensuring catalytic efficiency, and inhibiting hydrolysis scaling.

Inactive Publication Date: 2015-11-25
CHINA PETROCHEMICAL CORP
View PDF3 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although tetrabutyl titanate has a high catalytic activity, there are still the following deficiencies in the actual production process: ① by-product alkyl alcohol, such as butanol produced by the catalysis of tetrabutyl titanate, will accumulate in the reaction tower , affect the normal operation of the reaction tower; ②The discharge of alkyl alcohol from the wastewater will increase the burden of wastewater treatment; ③The alkoxide titanium catalyst is easy to hydrolyze, and the water generated in the esterification step will accelerate the hydrolysis, and the generated hydrolysis product titanium dioxide not only It is easy to accumulate on the wall of the reactor, which will affect the heat transfer and affect the quality of subsequent products
It has been reported in the literature that the use of nano-titanium dioxide as a catalyst can inhibit the hydrolysis of the catalyst while maintaining high catalytic activity, but the post-treatment is complicated and not suitable for industrial production
There are also reports in the literature that complexation methods are used to prepare hydrolysis-resistant catalysts, but the addition of complexing agents not only increases the cost of the product, but also may affect the reaction process and the application of subsequent products.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Continuous catalysis production method of PBT resin

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] 1.1 Preparation of catalyst

[0031] Add 15kg / hr of 1,4-butanediol and 1.5kg / hr of tetrabutyl titanate into the catalyst preparation tank. The temperature of the preparation tank is controlled at 90°C, the absolute pressure is controlled at about 10kPa, and the residence time is controlled at 2hr. The butanol collection tank 9 obtains a water-containing butanol solution, and the butanol flow rate is 0.33kg / hr. The catalyst solution is continuously discharged from the catalyst preparation tank 6 .

[0032] 1.2 Catalyst hydrolysis performance evaluation

[0033]The prepared catalyst solution sample and the tetrabutyl titanate catalyst sample were configured with four water concentration (0.5%, 1%, 2% and 3%) samples containing 0.5% titanium (titanium element) respectively, and observed the precipitation of the two, As shown in Table 1, it can be seen that the catalyst prepared in Example 1.1 has better hydrolysis resistance.

[0034] Table 1 Catalyst Hydrolysis Precipi...

Embodiment 2

[0041] Add 1000kg / hr of terephthalic acid and 638kg / hr of 1,4-butanediol into PBT beating tank 1, and stir to make PBT slurry 23. The PBT slurry 23 and 1.5kg / hr tetrabutyl titanate enter the PBT esterification reactor 2, and the esterification reaction is carried out at 200-250°C and 10-100kPa pressure (absolute pressure), and the water and side reactions produced by the reaction The generated THF and evaporated butanediol are separated in the PBT dehydration tower 4, water and THF come out from the top of the tower, and the rising steam is condensed in the top condenser 8, part of which is refluxed, and the rest enters the subsequent separation device for further separation THF and water, butanol flow in water is 0.65kg / hr. The butanediol at the bottom of the dehydration tower is returned to the PBT esterification reactor 2, and the PBT esterification product 24 generated by the esterification reaction enters the PBT pre-shrinkage reactor 3, and is pre-shrinked at 220-255°C a...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a continuous catalysis production method of PBT resin, and pulping, esterification, pre-polycondensation and polycondensation are carried out in order. The invention is characterized in that a catalyst conversion step is carried out before the pulping step, that is a compound with a structural formula Ti(OR)4 and 1, 4-butylene glycol are mixed and added into a catalyst preparation pot, in a condition with absolute pressure of 1-95kPa and temperature of 60-210 DEG C, a reaction is carried out for 0.5-10 hours, by-products ROH are removed, and a catalyst is obtained for a catalysis esterification reaction. According to the invention, a reaction between traditional Ti(OR)4 alkoxy titanium catalyst and 1,4-butylene glycol is carried out, a continuous reaction of PBT resin with a dihydric alcohol titanium catalyst is carried out, and at least one of alkoxys of the dihydric alcohol titanium catalyst is replaced by 1,4-butylene glycol. Hydrolysis resistance of the catalyst is good and catalysis effectiveness of the catalyst is guaranteed, simultaneously partial alkyl alcohols are recycled, and thereby reducing accumulation of alkyl alcohols in subsequent reactors, reducing influences on esterification reaction and dehydration process, reducing alkyl alcohols in waste water, and reducing COD of waste water.

Description

technical field [0001] The invention relates to a preparation method of PBT resin, in particular to a continuous catalytic production method of PBT resin, belonging to the technical field of PBT synthesis. Background technique [0002] Catalysts play a vital role in the production of polybutylene terephthalate (PBT). At present, the esterification step and polycondensation step in the PBT process route at home and abroad generally use alkoxy titanium catalysts, such as tetrabutyl titanate, tetraisopropyl titanate, etc. Although tetrabutyl titanate has a high catalytic activity, there are still the following deficiencies in the actual production process: ① by-product alkyl alcohol, such as butanol produced by the catalysis of tetrabutyl titanate, will accumulate in the reaction tower , affect the normal operation of the reaction tower; ②The discharge of alkyl alcohol from the wastewater will increase the burden of wastewater treatment; ③The alkoxide titanium catalyst is easy...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08G63/183C08G63/78C08G63/85
Inventor 李仁海张军赵付平黄娟唐建兴
Owner CHINA PETROCHEMICAL CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap